title: The use of the probiotic Lactobacillus rhamnosus GG and viral findings in the nasopharynx of children attending day care.
abstract: Limited data are available on the effects of probiotics on the nasopharyngeal presence of respiratory viruses in children attending day care. In this substudy of a randomized, double-blinded, placebo-controlled 28-week intervention study, nasopharyngeal swab samples were collected, on visits to a physician due to symptoms of infection, from children receiving control milk (N = 97) and children receiving the same milk supplemented with probiotic Lactobacillus rhamnosus GG (N = 97). The presence of 14 respiratory viruses was assessed by PCR methods, and viral findings were compared with symptom prevalences in the intervention groups. Rhinovirus was identified in 28.6% of 315 swab samples, followed by respiratory syncytial virus (12.4%), parainfluenza virus 1 (12.1%), enterovirus (8.9%), influenza A(H1N1)pdm09 (7.9%), human bocavirus 1 (3.8%), parainfluenza virus 2 (3.2%), adenovirus (2.9%), and influenza A(H3N2) (0.6%). The children in the probiotic group had less days with respiratory symptoms per month than the children in the control group (6.48 [95% CI 6.28-6.68] vs. 7.19 [95% CI 6.98-7.41], P < 0.001). Probiotic intervention did not reduce significantly the occurrence of the examined respiratory viruses, or have an effect on the number of respiratory symptoms observed at the time of a viral finding. Rhinovirus, respiratory syncytial virus, and parainfluenza virus 1 were the most common respiratory viruses in symptomatic children. Children receiving Lactobacillus rhamnosus GG had fewer days with respiratory symptoms than children in the control group, although probiotic intervention was not effective in reducing the amount of viral findings or the respiratory symptoms associated with viral findings.
authors.affiliation: Valio Ltd, Helsinki, Finland.
authors.forename: Minna
authors.initials: M
authors.lastname: Kumpu
authors.forename: Liisa
authors.initials: L
authors.lastname: Lehtoranta
authors.forename: Merja
authors.initials: M
authors.lastname: Roivainen
authors.forename: Esa
authors.initials: E
authors.lastname: Rönkkö
authors.forename: Thedi
authors.initials: T
authors.lastname: Ziegler
authors.forename: Maria
authors.initials: M
authors.lastname: Söderlund-Venermo
authors.forename: Hannu
authors.initials: H
authors.lastname: Kautiainen
authors.forename: Salme
authors.initials: S
authors.lastname: Järvenpää
authors.forename: Riina
authors.initials: R
authors.lastname: Kekkonen
authors.forename: Katja
authors.initials: K
authors.lastname: Hatakka
authors.forename: Riitta
authors.initials: R
authors.lastname: Korpela
authors.forename: Anne
authors.initials: A
authors.lastname: Pitkäranta
mesh_terms: D002648:Child; D002656:Child Day Care Centers; D002675:Child, Preschool; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D052201:Lacticaseibacillus rhamnosus / Q000276:immunology*; D008297:Male; D009305:Nasopharynx / Q000821:virology*; D010919:Placebos / Q000008:administration & dosage; D015995:Prevalence; D019936:Probiotics / Q000008:administration & dosage*; D016896:Treatment Outcome; D014777:Virus Diseases / Q000453:epidemiology / Q000473:pathology / Q000517:prevention & control* / Q000821:virology; D014780:Viruses / Q000145:classification / Q000302:isolation & purification*
chemical_list: D010919:Placebos
keywords: probiotic; respiratory infection; respiratory virus